Federal regulators sign cleanup plan for Idaho Superfund site

BOISE -- Federal regulators signed documents Tuesday outlining an interim cleanup plan for a polluted Superfund site in southeastern Idaho that they say will cost $57 million, take up to five years and might not be enough to protect the region's groundwater.

Philadelphia-based FMC operated a phosphorous production plant from the 1940s to 2001 on the Eastern Michaud Flats area of the Shoshone-Bannock reservation. The company blamed rising electricity costs for the shutdown of the plant where older technology made it less competitive.

The EPA announcement on Tuesday came on the heels of an initial cleanup plan dating to 1998, During the intervening years, the site has been plagued by other problems, including "burping" ponds, which are volatile waste repositories that produce phosphine gas that smells of rotten fish and can damage respiratory, nervous and gastrointestinal systems.

"EPA will continue to monitor the soil, air and groundwater to ensure the remedies outlined in this new cleanup plan are protective of people and the environment," the agency said in an e-mail announcing the plan. "Adjustments will be made if needed."

Jim Fitzwater, a spokesman for FMC, was not immediately available for comment.

Bill Bacon, an attorney for the Shoshone-Bannock Tribes, said Indian leaders would meet later Tuesday about the plan but don't believe it does enough to address the legacy of pollution left by FMC.

"This is a cover-up, not a cleanup," said Bacon. "We've always advocated that FMC needs to clean up."

The EPA says the cleanup will be paid for by the company and overseen by the agency and the Shoshone-Bannock tribes. The company had $3.4 billion in sales in 2011.

Priorities for the effort include reducing risks posed by the elemental phosphorus, metals, and radionuclides that are found in soils, fill and groundwater.

"This cleanup plan is considered 'interim' because additional actions may be required in the future to fully address groundwater quality goals," the EPA said.

A rain barrier will be installed to prevent precipitation from seeping through contaminated areas at the site near Interstate 86. And groundwater that could leave the site will be treated before it reaches springs and the Portneuf River.

"Elemental phosphorus from spills and process leaks during production, storage and handling areas has been detected down to 85 feet below the surface," the EPA said, adding that refined elemental phosphorous is unstable and can burn uncontrollably or explode when exposed to air.

Mountains of slag also emit gamma radiation, the EPA said, a potential hazard for humans and animals.